1. Field of the Invention
The present invention relates to a ratchet mechanism housing assembly for a ratchet screwdriver with improved strength to allow high torque operation.
2. Description of the Related Art
A wide variety of ratchet screwdrivers have heretofore been provided. For example, U.S. Pat. No. 4,290,328 to Clark issued on Sep. 22, 1981 discloses a ratchet handle including a composite ratchet gear; U.S. Pat. No. 4,621,718 to DeCarolis issued on Nov. 11, 1986 discloses a ratchet screwdriver; U.S. Pat. No. 4,696,208 to Lay issued on Sep. 29, 1987 discloses a direction-changeable structure of hand tool handle; and U.S. Pat. No. 5,379,873 to Shiao issued on Jan. 10, 1995 discloses a ratchet mechanism housing assembly for a ratchet screwdriver.
A common disadvantage of ratchet screwdrivers is that the pawls or members for actuating the ratchet wheel have a relatively small width such that they cannot provide sufficient torque for driving the ratchet wheel. The pawls or the ratchet wheel-actuating members might bend in some cases. In addition, the pawls or the ratchet wheel-actuating members have a relatively small contact area with the ratchet wheel and thus can be used in small torque operation only. The present invention is intended to provide an improved ratchet mechanism housing assembly that mitigates and/or obviates the above-mentioned disadvantage.